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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_007_782">&nbsp;</a>NAME</h4><blockquote>
mq_unlink - remove a message queue
(<b>REALTIME</b>)
</blockquote><h4><a name = "tag_000_007_783">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="mqueue.h.html">mqueue.h</a>&gt;

int mq_unlink(const char *<i>name</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_007_784">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>mq_unlink()</i>
function removes the message queue named by the pathname
<i>name</i>.
After a successful call to
<i>mq_unlink()</i>
with
<i>name</i>,
a call to
<i><a href="mq_open.html">mq_open()</a></i>
with
<i>name</i>
fails if the flag O_CREAT is not set in
<i>flags</i>.
If one or more processes have the message queue open when
<i>mq_unlink()</i>
is called, destruction of the message queue is postponed
until all references to the message queue have been closed.
Calls to
<i><a href="mq_open.html">mq_open()</a></i>
to re-create the message queue may fail
until the message queue is actually removed.
However, the
<i>mq_unlink()</i>
call need not block until all references have been closed;
it may return immediately.
</blockquote><h4><a name = "tag_000_007_785">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion,
the function returns a value of zero.
Otherwise,
the named message queue is unchanged by this function call,
and the function returns a value of -1 and sets
<i>errno</i>
to indicate the error.
</blockquote><h4><a name = "tag_000_007_786">&nbsp;</a>ERRORS</h4><blockquote>
The 
<i>mq_unlink()</i>
function will fail if:
<dl compact>

<dt>[EACCES]<dd>
Permission is denied to unlink the named
message queue.

<dt>[ENAMETOOLONG]<dd>

The length of the
<i>name</i>
string exceeds {NAME_MAX} while
_POSIX_NO_TRUNC is in effect.

<dt>[ENOENT]<dd>
The named message queue
does not exist.

<dt>[ENOSYS]<dd>
The function
<i>mq_unlink()</i>
is not supported by this implementation.

</dl>
</blockquote><h4><a name = "tag_000_007_787">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_007_788">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_007_789">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="mq_close.html">mq_close()</a></i>,
<i><a href="mq_open.html">mq_open()</a></i>,
<i><a href="mqueue.h.html">&lt;mqueue.h&gt;</a></i>,
<i><a href="msgctl.html">msgctl()</a></i>,
<i><a href="msgget.html">msgget()</a></i>,
<i><a href="msgrcv.html">msgrcv()</a></i>,
<i><a href="msgsnd.html">msgsnd()</a></i>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from the POSIX Realtime Extension (1003.1b-1993/1003.1i-1995)
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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